A decision on the redevelopment of Birmingham's New Street Station may not be made until next summer, the Government hinted last night.

It came as Edgbaston Labour MP Gisela Stuart issued a blunt warning in the Commons that it was "time for action" and that Birmingham could no longer afford further delays.

But Transport Minister Tom Harris said there was "a considerable amount of work still to be done" before the Government could give the project the green light.

Ms Stuart led a high-profile debate urging the Ministers to set out "a clear timetable" for an ambitious "Birmingham Gateway" scheme backed by MPs, the city council and business leaders.

She warned that New Street could not cope with the passengers it already has – and numbers are set to shoot up over the next 20 years. And the whole country will suffer as a result, because the station plays a key role in rail services from Scotland to London.

A refurbished New Street will include a larger passenger area, relieving the congestion that has in the past led to the closure of the station. The cost has been estimated at #500 million, including #380 million from public funds.

Ms Stuart said she was speaking on behalf of every one of Birmingham’s 11 MPs. She warned: "It is a station which, to pick up on the parlance of the day, is not fit for purpose."

Passenger numbers were growing fast, with a further 50 per cent growth forecast by 2026. But although the rail network itself could cope with demand, the station could not. Ms Stuart said: "In short, more passenger capacity is desperately needed at New Street."

The West Midland economy was losing up to #2.2 billion a year because of congestion on the roads.

The MP told Ministers: "Birmingham can no longer afford further delay on this matter. What we are asking for today is a speedy decision."

She added: "We are asking for a commitment of #380 million of public money now.

"It is time for decisive action, and I call on the Government to set out a clear timetable for the redevelopment of New Street."

MPs Khalid Mahmood (Lab Perry Barr) and Richard Burden (Lab Northfield) also urged the Government to back the refurbishment.

Mr Harris said the Government recognised New Street was "one of the most significant stations in the rail network of Great Britain."

He praised the Birmingham Gateway scheme, but added: "It does come at a high cost."

The Government would examine a business case currently being prepared by Network Rail and Birmingham City Council, he said. A decision might be included in a Transport White Paper to be published next summer.

"The Government is working with Birmingham City Council and Network Rail to find a sensible and affordable solution.

"No decisions have yet been made. There is a considerable amount of work still to be done before we reach such a stage."